I don't even... why in the world would it be important for a doctor to differentiate being struck by a dolphin or struck by orca (side note: orcas are dolphins!).
The only semi-plausible explanation is some weird insurance plan crafted for sea-world (et-al) staff. Neither Orcas nor (other) Dolphins were ever recorded to attack human beings out of captivity anyhow.
Unless an over-amorous encounter could be considered an attack. Seems to be a real problem, wonder if there's a code for 'loved to death(drowning) by dolphin'
It would be interesting to read a design document (or post-hoc technical analysis) that enumerates all the purposes that medical billing codes are used for. Maybe it would explain the easily-mocked craziness.
These are diagnosis codes, so it wraps up to national-level reporting - i.e. 35 people were injured by dolphins this year.
Also, insurance companies get crazy nit-picky with what types of treatment they'll cover for diagnoses. There is an entire industry around scrubbing claims and making sure treatment meets the diagnosis codes.
Insurance billing. These need to be exact in order to correlate to a) rates negotiated b) data collected for future underwriting c) exact repayment. Medical billing is a crazy world.
I've gotta believe that some dolphin injuries are more severe than some orca injuries.
At any rate, once the code describes a situation so specific that it may only classify a few injuries a year, what possible benefit may come from that?
So, an orca (9 codes) and a squirrel (6 codes) have their own damn codes but a friggin bear is in the other category?!? Heck, wolves, coyotes, bears, and mountain lions all don't have their own codes. I see a lobbying effort that needs to go on to show the true nature of dangerous animals in the US and quit hiding these attacks in the other category.
On the other hand, I do like the difference between cats and dogs:
W540XXA Bitten by dog, initial encounter
W540XXD Bitten by dog, subsequent encounter
W540XXS Bitten by dog, sequela
W541XXA Struck by dog, initial encounter
W541XXD Struck by dog, subsequent encounter
W541XXS Struck by dog, sequela
W548XXA Other contact with dog, initial encounter
W548XXD Other contact with dog, subsequent encounter
W548XXS Other contact with dog, sequela
W5501XA Bitten by cat, initial encounter
W5501XD Bitten by cat, subsequent encounter
W5501XS Bitten by cat, sequela
W5503XA Scratched by cat, initial encounter
W5503XD Scratched by cat, subsequent encounter
W5503XS Scratched by cat, sequela
W5509XA Other contact with cat, initial encounter
W5509XD Other contact with cat, subsequent encounter
W5509XS Other contact with cat, sequela